Managing Damping Off and Protecting Your Young Seedlings
Damping off refers to a plant disease that mainly affects seedlings and young plants. It is caused by various bacteria and fungi and leads to the collapse of the affected seedling’s leaves, stem, or root. Symptoms of damping off include:
- Thinning of sections of the stem
- Yellowing and/or of the leaves
- Wilting of young leaves
- The cotyledons may turn gray-brown
- Leaves may appear waterlogged and mushy
What Causes Damping Off?
This plant disease is caused by fungi and bacteria that thrive in moist and humid conditions. Pythium spp., Fusarium spp., and Rhizoctonia solani, are some of the most common fungi that trigger the disease in seedlings and young plants. Rhizoctonia solani and Fusarium spp. particularly cause damping off by killing the seedling at the soil line. On the other hand, Pythium spp. attacks from below the soil line – often targeting the root tips.
Controlling and Preventing Damping Off
The best way of controlling damping off in plants is by stopping it before it strikes. Once a plant or seedling has been infected, the disease may be difficult to put under control. Basically, selecting good quality seedlings and practicing good hygiene are all practices that can help in preventing the disease from infiltrating your seed bed in the first place.
Use of High-Quality Seeds
The use of treated seeds is the most effective way of containing damping-off diseases. Seeds may not always be free from pathogens and, therefore, seed treatment can help in the management of the disease. Besides helping in reducing the risk of seed contamination, seed treatment can help increase seedling vigor something that can boost the germination survival rates.
Employing Good Sanitation Practices
It is important to ensure that your gardening pots are sanitized in between uses. Unsterilized pots may harbor dangerous spores which can, in turn, find a soft landing in your garden and colonize it.
Sterilizing the pots is as easy as washing them in a mixture of bleach and water. For best results, sanitize all your other gardening equipment too.
Use Good Quality Potting Soil
Garden soil can provide a breeding ground for bacteria and fungi and it is, therefore, advisable to use solarized soil to ward off potential attacks. One should avoid re-using potted soil that has been previously under pathogen attack as this can harbor diseases.
Other than that, the soil should be light and fast-draining as waterlogging is often associated with a rise in incidences of damping off.
Good Cultural Practices for Seedling Plants
The fungi and bacteria responsible for damping off in plants thrive in moist conditions. Therefore, if the soil is always wet, it can create the perfect environment for the pathogens to grow and thrive. Overwatering should be avoided as having plants sit in water for days can provide the perfect breeding ground for disease-causing microorganisms.
Care should be taken to ensure adequate space is available between plants as a way to improve the circulation of air within the garden.
Plant Under the Right Conditions
Cold and wet soils not only create ideal conditions for pathogens to grow but also slow down the germination process. To encourage the healthy development of seedlings, it is imperative to plant seeds in warm, dry soil. Generally, the quicker the seedlings get to grow, the lower the likelihood of them experiencing damping off will get.
The idea is to get your plants past the most sensitive stage of development to be in the clear.
Careful Use of Fertilizers
Premature application of fertilizer or use of excess fertilizer can both work in favor of fungal development among your seedlings. Fertilizing the plants before they develop true leaves can particularly promote lush development of the seedlings leaving them more susceptible to fungal infections.
Use of slow-release fertilizers is recommended as it helps delay the supply of nutrients to the plants giving them enough time to develop past the most sensitive growth stage with minimal risk of damping off.
Over-fertilization should also be avoided as it might support the development of overly succulent leaves and shoots which could end up providing fertile breeding conditions for pathogens.
Conclusion
Damping off is a preventable plant disease whose management requires you to be proactive. The process should always begin with the selection of the right seeds and be followed up by good sanitation, cultural, and watering practices. Above all, care should be taken to keep the soil well-drained and over-crowding should be avoided.
